Integral cartons for the protection of fragile articles



July 1, 1958 J. F. cURRlvAN INTEGRAL CARTONS FORTI-IE PROTECTION OF FRAGILE ARTICLES 5 Sheets-Sheet l Filed sept. 9, 1955 INVENTOR This! E CunmvAN July 1, 1958 J. F. CURRIVAN INTEGRAL CARTONS FOR THE PROTECTION OF FRAGILE ARTICLES Filed Sept. 9, 1953 3 Sheets-Shea?l 2 INVENTOR E C UR RIVAN July 1, 1958 Filed Sept. 9. 1955 J. F. CURRIVAN INTEGRAL CARTONS FOR THE PROTECTION OF' FRAGILE ARTICLES 3 Shees--Sheetl 3 A'ITORNEYS United States Patent Otice 2,841,320 Patented July 1, 1958 INTEGRAL CARTONE; FOR THE PROTECTION F FRAGLE ARTICLES John F. Currivan, East Hampton, Conn.

Application September 9, 1953, Serial No. 379,180

Claims. (Cl. 229-39) This invention relates to containers and particularly to cartons for the protective packaging of frangible articles.

The invention contemplates primarily improvements in simple collapsible protective cardboard cartons for such articles as vacuum tubes, pharmaceutical vials and the -like and more specifically contemplates the improvements over the cartons claimed in my prior United States Patent No. 2,611,529.

While, through the unceasing etorts of a highly competitive industry, substantial gains have been made in the construction and production of cartons of this type, the manifold problems of creating a carton which meets the many and varied requirements of the industry has hitherto escaped complete solution.

The needs of the industry have imposed two basic inconsistent requirements on cartons of this type. First, such cartons must provide adequate protection for their contents against impact damage and breakage and second, the total cost of manufacturing and handling such cartons, which are ordinarily not re-nseable, must be kept at a minimum.

Prior efforts in the iield have met with some success in meeting one of these requirements but only at the sacrice of the other. Many prior cartons provide eX- cellent protection for fragile articles through the use of liners or other multiple-piece constructions. However, the cost of such cartons has either prevented their adoption by the industry or limited their use to specialized applications.

. On the other hand cartons which are susceptible of low cost manufacture and machine handling have, with the exception of the carton claimed in my prior Patent No. 2,611,529, failed to provide adequate protection for fragile articles.

The present invention is primarily concerned with improved cartons which aiord better protection of articles, such as certain television and radio tubes which are particularly sensitive to impact damage, and at the same time retain the cost advantages particularly those resulting from the adaptability to machine handling, offered by the carton of my prior patent.V

All forms of the cartons of the present invention are of one piece construction, are simple to make, collapse for empty shipment, lie flat in the magazine of loading machines, erect easily and receive their contents with a minimum of mechanical and manual manipulation.

It is accordingly a basic general object of the present invention to provide improved protective containers for fragile articles.

A more specific object of the present invention is the provision of novel protective containers which are fabricated from a one piece blank of minimum size and may be easily and inexpensively manufactured, erected, lled and closed entirely by machine operations.

A further object to the present invention is to provide novel protective cartons having integral protective inner flaps which are automatically opened and properly positioned during the normal machine erection of the carton.

Another object of the present invention is the provision of improved integral protective cartons having a protective inner partition section integral with the main carton walls which substantially surrounds and isolates the contents of the carton from the outer carton wall.

Still another object of the invention is the provision of novel integral protective cartons having, in certain forms of construction, integral protective inner partitions consisting of two separate inner llaps each integral with the assembled vcarton and requiring only one glue seam,

These and additional objects and the manner in which they are fullled will be apparent to those conversant lwith the art from a reading of the following description of certain preferred embodiment of the invention in conjunction with the subjoined claims and annexed drawings, in which,

Figure 1 is a plan View of a blank for one form of carton embodying my invention;

Figure 2 is a perspective view of an erected carton, a carton erected, for example from the blank shown in Figure 1, but representative of the general external appearance of a carton erected from any of the various forms of blanks throughout the drawings;

Figures 3, 4 and 5 are sectional views through a carton made from the blank shown in Figure 1, the location of the section line being indicated at 3 3 of said iigure,`the views showing the carton in fully collapsed, partially erected, and fully ereceted and loaded positions, respectively;

Figure 6 is a view similar to Figure 1 of a modified form of carton blank;

Figure 7 is a sectional view similar to Figure 5 and taken on line 7 7 of Figure 6 with the blank fully erected and loaded; l v l Figures 8 and 10 are views similar to Figures 1 and 6 showing further modied forms of carton blanks;

Figures 9 and 11 are sectionalviews similar to Figures 3 and 7 taken respectively on lines 9 9 `and 11 11 of Figures 8 and 1() with the carton blanks fully erected and loaded;

Figure 12 is a view similar to Figure 11 showing the carton empty; Y

Figures 13 and 17 are views similar'to Figures 1, 6, `8 and 10 showing still further modified forms of carton blanks;

Figures 14 and 18 are sectional views similar to Figures 3, 7, 9 and 11 taken, respectively, on lines 14-14 and 18 18 of Figures 13 and 17 with the respective carton blanks folded at; 1

Figure 15 is a sectional view similar to Figure 14 with the carton partially erected;

Figure 16 is a View similar to Figure 15 with the carton fully erected and loaded;

Figures 19 and 20 are end elevational views of fully erected cartons made from the blank shown in and partly in section on line 19 1l9 of Figure 17.

Referring to the drawings and first particularly to Figure 1, 2? indicates, generally au unfolded carton blank ready for gluing. The blank Yis usually made of cardboard and is manufactured by automatic machines which print, cut out the blanks from flat stock and perform operations such as scoring, perforating, cutting, notching, etc. A gluing machine completes the carton. t

Blank 20 comprises a body section 22 divided `into four contiguous rectangular side wall panels 24, 2,6, 28 and 30 by three parallel fold linesY 32a, 32b and `32C. These fold lines may be defined by regular scores, cut scores, or perforations depending on the type of board used and other factors indicating the necessity of one for sake of clarity. Y Y

Either or both of the extensions 54 and 56 preferably tuent or the other type of scorein a particular carton Vsuch as the degree of resiliency desired' of any particular fold. Y

It will be understood, therefore, that in this description the ,termffold line is used generically to .cover folds 'on all typesA of'scoriesY unless a particular typel is speci- 'callyfdesignated t f. i f Y One end of body section 22 carries an integral extension i consisting of apglue lap panel 33 joiningY panelV 24 along a foldlineV 34 anda protective inner'flap extension 36 'joining-panelj33 alongafold line 38. Y Y

A plurality'ofparallel fold lines 46a, 4Gb, 40C, 40d

V'and Y40e` divide section 36 Vinto sixelcngate panels 42,

44,46,` 48,150 and 52V; While six'panels are'shown for 'purposes of example, any number of panels'may be used, a Alargerjnumber resulting ina n'ior'e'nearlyr cylindrical protective flap.

c One end of pane-124 andthe opposite Yend of panel 28 carry integralclosure extensionsY S4'and 56, respectively, Y eachdivided into main yend closureap 58 and a tuck ap if board. Itv will be understood, however, that the straight Ytuc type of closure, i. e., wherein both closure llaps are on opposite ends-of the same wall panel may be used. Also, closure 'snaps may be used on all panels if a glued end carton is required.

Both ends of panels 26 and ondaryvclosure naps 64 separated from the respective panels by fold lines'66. These flaps fold inwardly and underlie main closure flaps58 whenV the erected carton is closed. Accordingly, the location of flaps 64 is dependent'on the location .of .the end closure aps and therefore `are placedon panels other than those carrying the main closure aps and/ or the panels opposite them inthe erected carton. I

In the forming of the carton blank, the aps 58 and 64A are preferably separated by a line cut 70 which has been exaggerated in thickness throughoutY the drawings (to the right in Figure l) as a unit, along the line 4th.`

onto panels 46, 44 and 42. The resulting double thickness is folded over to the right again along line 34 whereupon panels 28 and 30 are folded over, as a unit, to the left thus lapping the right hand edge of panel 30 over onto the glue lap 32, to which the machine has applied adhesive. Y

At this stage, the carton is completed in collapsed condition, ready for packaging or erection and appears substantiallyas shown in Figure 3.

Erection of the carton and the integral protective inner op 36 may be accomplished by squeezing the corner edges of the carton'dened by fold lines 32b and 34 as ndicatedby arrows 70. The carton panels Iirst assume the position shown in Figure 4 wherein the interior of said corner defined at line 32h contracts the inner ap 36at the fold line o. l Y Y With continued pressure on the,V corners, the opposed portions of flap 36 spread and buckle slightly on the fold lines 40a, 40b, 40d and 40e forming a protective liner of generally elliptical form'in the fully erected carton. In

this condition, the free edge of panel l52 is in sliding abut- Wifh Siderurgia ,24ans @were ne, liner,

will receive articles of a substantial range of cross-sectional i dimensions, Figure' 5' showingv the carton as it appears Vwhen containing a cylindrical'article such as vacuum tube 71 of the largest diameter it will safely accommodate. As can be seen from this figure, even the largest article accommodated by the carton is almost entirely enveloped `mutually opposite directions instead of the bending in l and isolated from the carton side walls vby the integral liner. i'

It is pointed out that, due to the inherent resiliency of the board, as soon as corners 32a and 32a` start to separate during theV erection process, the liner'panels assume aV generally doubleV convex lens shape .so that panels 42,VV 44, 46,V 48, 50 and 52 Vwill buckle radiallyaoutwardly Vin a double thickness toward o'ne'or the otherof corner` folds 32a and 32e. Further assurance that thelin'er panels will open properly maybe obtained by using cutscores This leaves the corresponding end of the erected carton Y 30 are provided with sec-V Y to definey fold'lines 40a, 40b, 40d and 40e, .the cutrbeing made onv the surface of the blank whichfaces outwardly 'inthe erected carton. However, it has been Vfound thatV regular scores function properly in this respect. Due to the simplicityof the blank, cutting, scoring, folding, gluing janderecting operations of the carton,` may be carried'out on standard machinery, Y Referring again to Fignire 1', the inner flap extension 36 of the carton blank is so cut that'the upper edge 76'comprises abroad V-shaped portion 78 and isv located `a. substantialdistance Yfrom .oneV end of the erec'tedcarton.

without an inner ilap, "adapting it particularly to thereception of such `articles asfradio vtubes having a-ba'se 'portion which'is larger lthancthe fragile glass portion and does not requireprotection. .The cut down ap extension also'eliminates interferencewith the tuck Hap 60'of thefend closure' extensionV 54 during closingwhile V-shape cutout V78V provides a' camming surface 'which f gnide'siand facilitates the insertion of the contents. of

, the carton into t-he yprotective, liner during the loading operation. Itis pointed out that this construction may be duplicated on the lower edge of extension 36. l However, for purposes of illustration in this disclosure, the lower edge is provided With a different form of camming edge Vachieved by forming an arcuate cutout slextending Y fromkfold line 40calmost to the free edge of panel 52. In the erectedV carton this cutout serves as a cam to guide the insertion of the contents, in the event that loading at this end of the carton is desired. Y 'Y The body portion 22 of the blank described theV externalbody portion of the carton and is the same for all forms of my novel cartons with such variations betweenV straight, reverse tuck or glued end closure ap larrangement and location as Ymay be desired and/or necessary in view of the particular form ofthe integral protective inner aps disclosed herein. For-this reasonV the remainder. of this descriptionv will be restricted pri of the flap 36 yfromrfold line 40e, respectively, to ,fold

line 38 and to the free edge of panel 52 -be greaterthan the diagonal distance :between fold lines 32b and 34v inthe erected carton, in order to achieve the automatic positioning of. the liner` during erection fof the carton. On the other hand, said respective dimensions must beA less than the distancebetween fold lines 32h and 34 Ywhen the carton is collapsed (see Figure 3) so that the 'carton' can be collapsed and will lie at.

Figure Y6 showsV a modification of the carton inner protective flap 36. In this vform of construction, Vpanel 42 extends the Ventire length ofthe glue lap 33, lthe Vfolduline 38therebetweenbeing defined preferably 'by above forms perforations in order to decrease the resistance to bendin'g resulting from the longer fold line although a regular or cut score may be used. Fold line 4Gb, Figure l, is eliminated so that panels 53 and 50 form a single large panel 84 approximately twice as wide as the remaining panels in the liner flap. The remainder of the carton structure is identical with that shown in Figure l, it being understood that the same variations in the location of flaps on the carton body and camming surfaces and types of camming surfaces on the liner 36 may be resorted to. The erecting action is also the same except that, in a fully erected carton containing an article of maximum permissible dimension, the inner liner assumes the position shown in Figure 7 wherein the large flap 84 is at against the outer side wall 26. The elimination of fold line 4Gb leaves the section of the inner liner comprising panels 84 and S2 with less flexibility and therefore the liner tends to hold smaller articles more securely. Forming panel 42 coextensive with the glue lap 33 decreases the area of differential thicknesses of the carton from end to end when folded ilat and therefore decreases the tendency of a stack of folded cartons, for example, in the magazine of a carton loading machine, t0 tilt.

A third form of the invention which is preferred 4for packaging miniature tubes is shown in Figures 8 and 9 wherein the inner protective ap 36 is specifically adapted for loading from the lower end as viewed in this figure. Accordingly, the camming edges 78 are provided on the lower edge 80 of the inner flap while the upper edge 76 lies in a plane parallel to but spaced from the upper edge of the carton by a distance equal to the length of the tuck flap 60 thereby eliminating the possibility of interference between the inner protective flap and the tuck flap while the carton is being closed. inner flap extension 36, as in the species illustrated in Figures l through 5, is divided into six panels and, while the overall length of the flap from fold line 38 to the free edge of panel 52 is the same, as is the distance between fold 40C and the free edge, the relative widths of the panels are somewhat different, resulting in a different configuration of the inner flap when fully erected and containing a cylindrical article 71 of maximum permissible diameter as shown in Figure 9.

An additional form of inner tiap construction according to the present invention which is preferred for the packaging of longer tubes provided with bases, is shown in Figures lO, ll and l2 which form is particularly versatile in that it may not only be used to hold articles of varying diameters, but also to space one end of a fragile article from the corresponding end of the carton, or to package two companion articles such, for example, as a medicine vial and a medicine dropper. This form of construction is generally similar to that shown in Figure 6 except that panel 42 is not coextensive with the glue lap 32. Instead a separate partition ap 86 is formed on the glue lap adjacent one end of panel 42 and foldable on the common fold line 33 therewith or on a fold line space from line 32.

The precise lateral dimension of partition flap 86 may be varied to suit the requirements of the particular products to be packaged. Inasmuch as iiap S6 is divided from panel 42 by a line cut 88, it is free to assume an angular position in the erected carton independent of panel 42. The precise angle of ap 6 in the carton is dictated by its lateral dimension. Thus, if the width of flap 86 is such that, added to the width of lap 32, it does not exceed the width of panel 30, it will lie flat against panel 30, and has the same e'ect of improving the stacking characteristics of folded cartons as the full length one piece panel 42 in Figure 6. As the width of panel 86 is increased, its free edge will slidably contact side panel 28 and it will occupy a position in the erected carton at increasingly greater angles to side wall 6 30. Additional aps similar to aps 86 may also be used on separate or common fold lines.

Referring to Figure 12, partition panel 86 is shown as it appears when its width plus the width of the glue lap 32 is greater than the width of side wall panel 30, under which conditions it cuts across the zone of the carton enveloped by the inner flap 36. If an article having two diameters is to be placed in the carton it would be inserted with the smaller diameter toward the end of the carton containing flap 86 and would bear against it while the larger portion of the article would occupy the opposite end of the carton, where it would be enveloped by all the panels of the protective flap. By increasing the length of flap 86 it can be made to extend substantially across the interior of the carton and utilized to space the article placed in the carton from one end thereof. Also, by proper selection of the length of panel 86 the interior of the carton can be effectively divided into Zones such as 90 and 92 to receive, for example, a medicine bottle and a medicine dropper.

In this particular form of construction, the length of the inner protective flap from fold line 40o to the edge of panel 52 is increased over the corresponding dimension of the preceding embodiments by a small increase in the width of panel 50 and a substantially larger increase in the Width of panel 52. Consequently, the inner protective flap, in the erected carton, takes the form shown in Figures l() and l2, providing more complete envelopment of the contents thereof.

The foregoing embodiments of myinvention all utilize a liner formed of a single integral inner ap extension formed on the free edge of the glue lap of the carton body portion. The following modifications, while they still require but a single glue seam in the formation of the carton and are integral in construction have a protective inner liner formed by inner flap extensions on both ends of the body portion of the carton blank.

One of these forms is shown in Figures l3-l 6, inclusive. Referring particularly to the carton blank shown in Figure 13, it will be seen that the body portion 22 is identical with those in all preceding embodiments; however, each end of the body portion is provided with inner protective flaps 94 and 96 formed as integral parts thereof. Flap 94 is contiguous with side wall panel 24 and separated by fold lines 98a, 98h, and 98e into three panels 100, 102 and 104 of substantially equal width. Panel 30 at the opposite end of the carton blank carries the glue lap 33 which, in this case, is extended to form iiap 96 divided by fold lines 106g and 10617 into a pair of panels 108 and of substantially equal width. While the upper and lower edges of ap extensions 94 and 96 are illustrated as incorporating notches 111, it will be appreciated that these edges may be cut back and/or provided with other camming surfaces in the manner previouslyY described. This form of carton may be folded for gluing by folding inner flap extension 94 as a unit along .line 98a to the right; folding 'extension 96 as a unit along line 106:1 to the left; folding the double thickness comprising extension 96, panel 30 and glue lap 33 to the left on line 32e; and then folding the body panel 24 to the right on line 32a so that the edge of panel 100 adjacent line 98a overlaps glue lap 33. A suitable adhesive may be applied to either or both of the lapped surfaces before, during or after the folding operation,

Thus the carton is completed in the flat, folded condition shown in Figure 14. Erection may be accomplished by squeezing the corners defined by fold lines 32a and 32C toward each other whereupon, due to the resiliency of the board at the fold lines, the panels of the inner protective aps assume the intermediaterposition shown in Figure l5. Under continued pressure side wall panel 24 acts on fold lines 98h and 10611 tending to force the free ends of panels 104 and 11!) into corner 32e. Then fold line 106b cams along side wall panels 30 Ato 110 to move out of-thecorner alongside wallypanel 28 to approximately the mid-point thereof pushing the free end of panel Y104 ahead of it thus fully erecting the innerV aps into the position shown in Figure 16. Y *A -f It will be noted that in this form of carton, a cylindrical object placed therein has only line` contact with panels 102, 104, 108 Vand 110 at approximately'the'mid-points thereof, lwhich points are completely isolated hom contact with theouter carton panels. A The remainder of the contained object is spacedat all points from those portions'of the protective'inner liner which are in contact with the outer cartonwall. The free endsof panels 104 and 110, being insliding abutment with panel 28 provide a high degree of resiliency and ilexibility permitting a substantial range in the size of objects which may be contained in the carton. Y e v Another form of improvedcarton utilizing a divided protective inner ap is shown in Figures l7-20, inclusive, wherein a single panel 108 extends foldably from the glue lap 33 at one end of body portion 22 of the carton blank and four foldably related panels 100, 102,104 and 110 extend from the opposite end. A relatively-,shallow V-shaped notch 112 in the adjacent ends of panels 102 and 104, inclined upper end 114 on panel 110 and a more steeply inclined upper end 116 on panel 108 cornbine in the erected carton to provide an eicient camming surface for guiding an article being loaded in the carton into the protective liner. As can be seen from Figure 20, the high points on theupper edges of the inner protective aps form, in the erected carton, a series of peaks spaced cir/cumferentially` about the interior of the carton and connected byY sloping surfaces giving the elect of a funnel for guiding the article being inserted.' Y

An alternative form of camming surface construction is shown `on the lower edge ofthe inner protective ilaps wherein a smaller number of larger Vpeaks is achieved by forming the ends of panels 102, 104 and 110, with alternately directed arcuate edges 118 meeting at fold lines 98e` and 98d and forming the corresponding end of-panel '108' an inclined edge 120. In the erected carton, these edges are circumferentially disposed to guide thevobject being inserted into the protective liner. The carton blank is folded in a manner similar to that already described for the'ernbodiment-shown in'Figure 13. Thus, panels- 100, 102, 104 and 110' are folded as a unitA to the right along line 98a and panel 11W-is folded back (to the left) on panel 104 along line 98d. Then panel 108 is folded overV (to the left) onto glue lap 33 along line 106b; lpanel/30, glue lap 33 and panel 108 are then folded as a unit to the left along the line 32C; and panel 24 carrying Vthe respective inner ap extension, folded -as above described is folded to the righton line 32d whereupon Vthe edge of panel 100 adjacent line 98a will overlap the glue panel 33. yAs in the foregoing embodiments a suitable adhesive is applied to either or both ,of4 the lapping surfaces before, during or after Vthe folding operation. y i

At this stage the folded carton appears as shown in Figure 18 and may be erected by the squeezing corners defined by fold lines 32a and 32C.

tion shown in Figure 19 due to the resiliency of the fold lines. As an article is inserted into the flap and actsY on the camming surfaces above described the flaps areV Vpushed into the position shown in Figure 20. The probut a single glue seam, fold at for stacking', aeeasilyV Whenythercarton is Y fully erected the inner respective'llaps will take the posifolded-glued, loaded, and closed by operationsca'pable of Y being performedby standardcarton making and loading machinery.Y Y Y I f The inventionmay be embodied in'other specific forms without departing'from the Vspirit: o'r. essential characteristics thereof.V `The present .embodiments are therefore to beconsidered in all respects as illustrative'and not restrictive,` the scope yof the inventionbeing indicated Vby the appended claims rather than by the foregoing description, and all changes which come-within the. meaning and range of'equivalency of the claims are therefore intended to be embraced therein.

What is claimed andy desired'to be secured by United States Letters Patent is:

l. A collapsible -cartonof substantially rectangular cross-section for Ythe. protective containment o'f fragile articles consisting of a single blank having r'st, second, f third and fourth side wall panels separated by foldlines and angularly related in theV erected carton, at least-two end closure aps. having foldable extensions, 'said endY closure aps extending integrally from the ends'of certain of said'iirst, second and fourth side wall panels only,V

additional-end closure naps extending integrally from the opposite Yends of two of the sidewall panels which-'are opposed in the erected carton and, in the erectedcar-ton, are immediately adjacent the panels to which saidiirst mentioned end closure aps are attached, said end closure iiaps being adapted to provide end wallsy of the erectedr closed carton, a gluelap'panel extending from saidfourth sidewallV panel and adapted to be overlapped "byysaid first side wall panel and be rigidly secured thereto,-said glue lap panel being of substantially less width than said first side wall panel, andan Vinternaltlap terminating in 'i a free edge and extending inwardlyfromsaid glue' lapY ini termediate the edges of said first side? wall panel, said internal iiap consisting of a plurality of elongate panels foldably related on fold lines parallel to the axis .ofthe erected carton and adapted to substantially envelop fan article placed in the carton, the total width of said panels j on each side of'one of said fold'rlinesV being greater than thediagonal of the erected carton and less than the 'width of two adjacent side wall panels whereby said innerliap will fold fiat on said one fold line when'said carton' is folded on the fold Vlines between said -iirst `and, Vfourth and said second and third side wall panels, and the width of portion of said internal flap between saidfree edge and said one fold line being such that portion of Y said ilap slidably contacts" the inner surface of'said'gthird sidewall section and saidL free edge'slidablycontacts said fourth side wall panel on a line substantially spaced from a `fold line between said fourth side Wall panel and said glue lap when saidcarton is erected and loaded.

2'. The carton defined in claim, 1 whereinV at' least one lateral Vedge of said inner ap has a shallow angular cutl out portion having its apex on said one fold line whereby an article-being inserted into the carton exerts a camming action against said cut-out edge portion to facilitate loading Vof the carton. j w f 3. TheY .carton defined in'claim 1 wherein at leastone lateral edge of said inner ilap has a shallow arcuate cutout portion extending from said one fold line substantially to the free end of saidinner ap whereby Van article being inserted into the Vcarton exerts a cammingV action against said cut-out edge portion to facilitate loading of a the carton.

V4. The carton definedin claim 1 wherein at leastthe. panel of the inner flap adjacent the glue lap is substantially shorter'than the glue lap, an additional inner partition ap foldably extending from the portion of the glue lap extending beyond said. inner Vilap panel, the totalwidth of said glue lap and additionalpartition flap exceeding the width of said first side wall-panel whereby in the erected carton, said additional partition ap extendsat anl angle to said iirst side wall panel and has its free' end 7 5T in sliding abutment with saidY second side wall panel.

5. A collapsible carton of substantially rectangular cross section for the protective containment of fragile articles consisting of a single blank having rst, second, third and fourth side wall panels separated by fold lines and angularly related in the erected carton; a glue lap panel extending from said fourth side wall panel and adapted to be overlapped by the first side Wall panel and to be rigidly secured thereto, said glue lap panel being of substantially less width than said rst side wall panel; and an internal flap extending integrally from said glue lap, terminating in a free edge slidably contacting said fourth side wall panel along a line substantially spaced from the fold line between said fourth side wall panel and said glue lap panel and consisting of a plurality of elongate contiguous panels foldably related along fold lines parallel to the longitudinal axis of the erected carton, the total width of said inner flap panel and the spacing of said fold lines being such that said inner flap slidably contacts each of said second and third side wall panels on one of the inner panel fold lines and will substantially envelope an article contained in the carton, one of said inner ap fold lines being substantially at the midpoint of the flap permitting the flap to fold in half along said one fold line, the width of said inner flap so folded being greater than a diagonal of the erected carton passing through the corner of the body portion between said first and fourth side Wall panels and less than said diagonal when said carton is folded iiat, whereby movement of the corners of the body portion dening said diagonal toward each other during erection of the carton automatically unfolds, erects, and positions said inner protective ap.

References Cited in the file of this patent UNITED STATES PATENTS 1,238,364 Wallace Aug. 28, 1917 1,704,739 Grigg Mar. l2, 1929 2,539,966 Orovig Jan. 30, 1951 2,611,529 Currivan Sept. 23, 1952 2,620,116 McDonough Dec. 2, 1952 2,714,981 Leavens Aug. 9, 1955 2,732,123 Bolding Ian. 24, 1956 2,732,996 Pantalone Jan. 31, 1956 FOREIGN PATENTS 241,097 Great Britain Oct. l5, 1925 258,925 Great Britain Sept. 24, 1926 

